The present invention relates to the field of starter mechanisms in general and, more particularly, to a frictional gripping mechanism for engaging a starter motor and an enging flywheel disc.
Modern motor vehicles employ an electric starter gearing mechanism for cranking an internal combustion engine. Such starter gearing mechanisms generally comprise an electric motor operably engagable to the engine flywheel disc by gear teeth on the periphery of the flywheel disc and a pinion gear mounted on a helical thread of the shaft of the electric motor. When the engine starting circuit is energized, the starting motor initiates rotation of the shaft. The resting inertia of the pinion gear causes its rotation to lag the rotation of the starting motor shaft so that the pinion gear is advanced axially along the helical thread of the shaft. The teeth of the pinion gear are carried into meshing engagement with the gear teeth on a periphery of the flywheel disc, thereby rotating the flywheel to start the engine.
In order to insure proper meshing engagement of the gear teeth of the pinion with that of the flywheel disc, it has become necessary to incorporate complicated and exacting gear tooth arrangements within the starter gearing. The resulting conventional engine starting gearing mechanism is, therefore, not only expensive, but also exhibits noisy operational characteristics. Further, the conventional starter gearing mechanism as installed in present motor vehicles, results in a substantial component of in thrust imparted to the flywheel disc.